// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This class represents contextual information (cookies, cache, etc.)
// that's useful when processing resource requests.
// The class is reference-counted so that it can be cleaned up after any
// requests that are using it have been completed.

#ifndef NET_URL_REQUEST_URL_REQUEST_CONTEXT_H_
#define NET_URL_REQUEST_URL_REQUEST_CONTEXT_H_

#include <memory>
#include <set>
#include <string>

#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/non_thread_safe.h"
#include "net/base/net_export.h"
#include "net/base/request_priority.h"
#include "net/http/http_network_session.h"
#include "net/http/http_server_properties.h"
#include "net/http/transport_security_state.h"
#include "net/log/net_log.h"
#include "net/ssl/ssl_config_service.h"
#include "net/url_request/url_request.h"

namespace net {
class CertVerifier;
class ChannelIDService;
class CookieStore;
class CTPolicyEnforcer;
class CTVerifier;
class HostResolver;
class HttpAuthHandlerFactory;
class HttpTransactionFactory;
class HttpUserAgentSettings;
class NetworkDelegate;
class NetworkQualityEstimator;
class SdchManager;
class ProxyService;
class URLRequest;
class URLRequestBackoffManager;
class URLRequestJobFactory;
class URLRequestThrottlerManager;

// Subclass to provide application-specific context for URLRequest
// instances. Note that URLRequestContext typically does not provide storage for
// these member variables, since they may be shared. For the ones that aren't
// shared, URLRequestContextStorage can be helpful in defining their storage.
class NET_EXPORT URLRequestContext
    : NON_EXPORTED_BASE(public base::NonThreadSafe) {
public:
    URLRequestContext();
    virtual ~URLRequestContext();

    // Copies the state from |other| into this context.
    void CopyFrom(const URLRequestContext* other);

    // May return nullptr if this context doesn't have an associated network
    // session.
    const HttpNetworkSession::Params* GetNetworkSessionParams() const;

    std::unique_ptr<URLRequest> CreateRequest(
        const GURL& url,
        RequestPriority priority,
        URLRequest::Delegate* delegate) const;

    NetLog* net_log() const
    {
        return net_log_;
    }

    void set_net_log(NetLog* net_log)
    {
        net_log_ = net_log;
    }

    HostResolver* host_resolver() const
    {
        return host_resolver_;
    }

    void set_host_resolver(HostResolver* host_resolver)
    {
        host_resolver_ = host_resolver;
    }

    CertVerifier* cert_verifier() const
    {
        return cert_verifier_;
    }

    void set_cert_verifier(CertVerifier* cert_verifier)
    {
        cert_verifier_ = cert_verifier;
    }

    ChannelIDService* channel_id_service() const
    {
        return channel_id_service_;
    }

    void set_channel_id_service(
        ChannelIDService* channel_id_service)
    {
        channel_id_service_ = channel_id_service;
    }

    // Get the proxy service for this context.
    ProxyService* proxy_service() const { return proxy_service_; }
    void set_proxy_service(ProxyService* proxy_service)
    {
        proxy_service_ = proxy_service;
    }

    // Get the ssl config service for this context.
    SSLConfigService* ssl_config_service() const
    {
        return ssl_config_service_.get();
    }
    void set_ssl_config_service(SSLConfigService* service)
    {
        ssl_config_service_ = service;
    }

    // Gets the HTTP Authentication Handler Factory for this context.
    // The factory is only valid for the lifetime of this URLRequestContext
    HttpAuthHandlerFactory* http_auth_handler_factory() const
    {
        return http_auth_handler_factory_;
    }
    void set_http_auth_handler_factory(HttpAuthHandlerFactory* factory)
    {
        http_auth_handler_factory_ = factory;
    }

    // Gets the http transaction factory for this context.
    HttpTransactionFactory* http_transaction_factory() const
    {
        return http_transaction_factory_;
    }
    void set_http_transaction_factory(HttpTransactionFactory* factory)
    {
        http_transaction_factory_ = factory;
    }

    void set_network_delegate(NetworkDelegate* network_delegate)
    {
        network_delegate_ = network_delegate;
    }
    NetworkDelegate* network_delegate() const { return network_delegate_; }

    void set_http_server_properties(
        HttpServerProperties* http_server_properties)
    {
        http_server_properties_ = http_server_properties;
    }
    HttpServerProperties* http_server_properties() const
    {
        return http_server_properties_;
    }

    // Gets the cookie store for this context (may be null, in which case
    // cookies are not stored).
    CookieStore* cookie_store() const { return cookie_store_; }
    void set_cookie_store(CookieStore* cookie_store);

    TransportSecurityState* transport_security_state() const
    {
        return transport_security_state_;
    }
    void set_transport_security_state(
        TransportSecurityState* state)
    {
        transport_security_state_ = state;
    }

    CTVerifier* cert_transparency_verifier() const
    {
        return cert_transparency_verifier_;
    }
    void set_cert_transparency_verifier(CTVerifier* verifier)
    {
        cert_transparency_verifier_ = verifier;
    }

    CTPolicyEnforcer* ct_policy_enforcer() const { return ct_policy_enforcer_; }
    void set_ct_policy_enforcer(CTPolicyEnforcer* enforcer)
    {
        ct_policy_enforcer_ = enforcer;
    }

    const URLRequestJobFactory* job_factory() const { return job_factory_; }
    void set_job_factory(const URLRequestJobFactory* job_factory)
    {
        job_factory_ = job_factory;
    }

    // May return nullptr.
    URLRequestThrottlerManager* throttler_manager() const
    {
        return throttler_manager_;
    }
    void set_throttler_manager(URLRequestThrottlerManager* throttler_manager)
    {
        throttler_manager_ = throttler_manager;
    }

    // May return nullptr.
    URLRequestBackoffManager* backoff_manager() const { return backoff_manager_; }
    void set_backoff_manager(URLRequestBackoffManager* backoff_manager)
    {
        backoff_manager_ = backoff_manager;
    }

    // May return nullptr.
    SdchManager* sdch_manager() const { return sdch_manager_; }
    void set_sdch_manager(SdchManager* sdch_manager)
    {
        sdch_manager_ = sdch_manager;
    }

    // Gets the URLRequest objects that hold a reference to this
    // URLRequestContext.
    std::set<const URLRequest*>* url_requests() const
    {
        return url_requests_.get();
    }

    // CHECKs that no URLRequests using this context remain. Subclasses should
    // additionally call AssertNoURLRequests() within their own destructor,
    // prior to implicit destruction of subclass-owned state.
    void AssertNoURLRequests() const;

    // Get the underlying |HttpUserAgentSettings| implementation that provides
    // the HTTP Accept-Language and User-Agent header values.
    const HttpUserAgentSettings* http_user_agent_settings() const
    {
        return http_user_agent_settings_;
    }
    void set_http_user_agent_settings(
        HttpUserAgentSettings* http_user_agent_settings)
    {
        http_user_agent_settings_ = http_user_agent_settings;
    }

    // Gets the NetworkQualityEstimator associated with this context.
    // May return nullptr.
    NetworkQualityEstimator* network_quality_estimator() const
    {
        return network_quality_estimator_;
    }
    void set_network_quality_estimator(
        NetworkQualityEstimator* network_quality_estimator)
    {
        network_quality_estimator_ = network_quality_estimator;
    }

    void set_enable_brotli(bool enable_brotli) { enable_brotli_ = enable_brotli; }

    bool enable_brotli() const { return enable_brotli_; }

    void set_enable_referrer_policy_header(bool enable_referrer_policy_header)
    {
        enable_referrer_policy_header_ = enable_referrer_policy_header;
    }

    bool enable_referrer_policy_header() const
    {
        return enable_referrer_policy_header_;
    }

private:
    // ---------------------------------------------------------------------------
    // Important: When adding any new members below, consider whether they need to
    // be added to CopyFrom.
    // ---------------------------------------------------------------------------

    // Ownership for these members are not defined here. Clients should either
    // provide storage elsewhere or have a subclass take ownership.
    NetLog* net_log_;
    HostResolver* host_resolver_;
    CertVerifier* cert_verifier_;
    ChannelIDService* channel_id_service_;
    HttpAuthHandlerFactory* http_auth_handler_factory_;
    ProxyService* proxy_service_;
    scoped_refptr<SSLConfigService> ssl_config_service_;
    NetworkDelegate* network_delegate_;
    HttpServerProperties* http_server_properties_;
    HttpUserAgentSettings* http_user_agent_settings_;
    CookieStore* cookie_store_;
    TransportSecurityState* transport_security_state_;
    CTVerifier* cert_transparency_verifier_;
    CTPolicyEnforcer* ct_policy_enforcer_;
    HttpTransactionFactory* http_transaction_factory_;
    const URLRequestJobFactory* job_factory_;
    URLRequestThrottlerManager* throttler_manager_;
    URLRequestBackoffManager* backoff_manager_;
    SdchManager* sdch_manager_;
    NetworkQualityEstimator* network_quality_estimator_;

    // ---------------------------------------------------------------------------
    // Important: When adding any new members below, consider whether they need to
    // be added to CopyFrom.
    // ---------------------------------------------------------------------------

    std::unique_ptr<std::set<const URLRequest*>> url_requests_;

    // Enables Brotli Content-Encoding support.
    bool enable_brotli_;

    // Enables parsing and applying the Referrer-Policy header when
    // following redirects. TODO(estark): remove this flag once
    // Referrer-Policy ships (https://crbug.com/619228).
    bool enable_referrer_policy_header_;

    DISALLOW_COPY_AND_ASSIGN(URLRequestContext);
};

} // namespace net

#endif // NET_URL_REQUEST_URL_REQUEST_CONTEXT_H_
